***behavior gen_evp
 **elasticity isotropic
   young 205000.
   poisson 0.3
 **potential gen_evp ep
  *flow plasticity
  *criterion mises % or tresca 
   *isotropic linear
      R0  100.
      H  0. % 2000.
 **coefficient
   masvol 8.08e-9
***return